Atomizing nozzle, particularly for oil-burners

ABSTRACT

The invention relates to an atomizing nozzle having a tubularly shaped housing with an outlet orifice at one end thereof. An annularly shaped member having a frustoconically shaped backing surface is adjacent the orifice. A frustoconically shaped shell member is held in position against the backing surface with a screw member having a frustoconically shaped male surface. Grooves or slots are provided in the shell member and either or both of the frustoconically shaped surfaces are cooperable with the grooves or slots to provide fluid flow passages.

United States Patent Petersen et al.

[ 1 June 13, 1972 ATOMIZING NOZZLE, PARTICULARLY FOR OIL-BURNERSInventors: Jorgen Hartvig Petersen, Nordborg; Leif Viggo Sturlason,Sonderborg, both of Denmark Assignee: Danfoss A/S, Nordberg, DenmarkFiled: Jan. 13, 1971 Appl. No.: 106,054

Foreign Application Priority Data [56] References Cited UNITED STATESPATENTS 2,746,801 5/1956 Curran ..239/552 X 2,484,037 10/1949 King..239/493 Primary Examiner-M. Henson Wood, Jr. Assistant ExaminerEdwinD. Grant v AttorneyWayne B. Easton ABSTRACT The invention relates to anatomizing nozzle having a tubularly shaped housing with an outletorifice at one end thereof. An annularly shaped member having afrustoconically shaped backing surface is adjacent the orifice. Afrustoconically shaped shell member is held in position against thebacking surface with a screw member having a frustoconically shaped malesurface. Grooves or slots are provided in the shell member and either orboth of the frustoconically shaped surfaces are cooperable with thegrooves or slots to provide fluid flow passages.

Feb. I8, 1970 Germany ..P 20 07 342.1

US. Cl ..239/544, 239/590.3, 239/596 Int. Cl ..B05b 1/26 Field of Search..239/544, 552, 553, 553.3, 568, 239/590, 590.3, 590.5, 596, 598, 601,554, 555, 493; 138/40 PATENTEDJUN 13 1912 saw 10F ATOMIZING NOZZLE,PARTICULARLY FOR OIL- BURNERS The invention relates to an atomizingnozzle, particularly for oil-bumers and comprising passages which areformed between a nozzle cone and a corresponding backing element.

In pressure-operated atomizing nozzles, the quantity of materialexpelled, the form of the atomizing cone and the even distribution ofthe liquid in the atomizing cone depend very considerably upon thepassages which are disposed directly downstream of the outlet orifice ofthe nozzle. It is known to form these passages by milling grooves in thenozzle cone, these grooves being covered by the backing element. Thismethod of manufacture is however time-consuming, since several grooves,e.g. three or four, have to be machined in each nozzle cone. Since thepassages are only small, even slight lack of precision leads todefective operation of the nozzle. Such lack of precision occurs forexample when the milling tool is worn, when it undergoes slight changesin its lateral and vertical settings, when a burr is formed duringmilling, when the passages are deformed as the result of excessivesurface pressure during fitting, and so on.

The object of the invention is to provide an atomizing nozzle thepassages in which can be produced at considerably less expense and witha greater degree of precision.

According to the invention, this object is achieved by providing thepassages in a substantially frusto-conical insertav ble shell which isclamped between the nozzle cone and the backing element.

Although an insertable sheel of this kind constitutes an additionalcomponent, since it is thin-walled however, the passages can be formedin it with great precision and without any milling operation. Despiteclose dimensional tolerances, a shell of this kind is particularlysuitable for manufacture by mass-production methods. Since the nozzlecone can take the form of a simple turned part, the total cost ofmanufacture is lower than in the case of the known atomizing nozzles.

In a preferred embodiment the passages are formed by slotting theinsertable shell and by covering part of the length of the slots on bothsides by the nozzle cone and the backing element. In this arrangementthe cross section of the passages is determined by the thickness of theshell and the width of the slots.

In another embodiment in which the shell has a somewhat greater wallthickness, the passages are formed by grooves in the shell and bycovering part of their length by the nozzle cone or by the backingelement.

Very great precision can also be achieved in mass production if theinsertable shell is a drawn product, from which the passages are stampedout or in which they are impressed. In particularly, the insertableshell can be made of hardened steel, e.g. spring steel. Sharp edges andthe like can be smoothed off by means of an electrolytic coating.

Another method, very useful in mass production operations, is thatwherein the insertable shell is a sintered product.

The invention will now be described in more detail by reference to twoembodiments illustrated in the drawing, in which:

FIG. 1 is a schematic longitudinal section through an atomizing nozzleaccording to the invention.

F IG. 2 is a perspective illustration of the insertable shell employed,

FIG. 3 is a longitudinal section through another embodiment of theatomizing nozzle, and

FIG. 4 is a perspective illustration of the used in the nozzle of FIG.3.

Referring to FIG. 1, the atomizing nozzle has a casing 1 containing anoutlet orifice 2. In the interior there is provided an annular nozzlelining 3 with a conical backing face 4. A nozzle cone 5 can be pressedagainst the backing face 4 with the help of a screw 6. Between thenozzle cone 5 and the backing face 4 there is clamped an insertableshell 7. This shell is made of hardened steel sheet and contains threeslots 8 which are covered over part of their length by the nozzle cone 5on the one side and the backing face 4 on the other. In this way,

passages disposed along the length of a cone are formed in a veryaccurate manner. The slots 8 extend as far as the endface 9 of theshell, so that the passages open towards the nozzle orifice 2.

In the present embodiment, the insertable shell is made of sheet metal.It is produced from a flat sheet metal blank by stamping and drawing.The sheet metal is then hardened and provided with an electrolyticcoating. Fitting is very' simple since the shell is automaticallyadjusted to give the correct position by tightening the screw 6.

The casing is screwed in the usual way on to a nozzle rod, notillustrated. Oil is fed through the inlet orifice l0,passes alongpassages 11 in the screw 6 and into the distributing chamber 12, whenceit passes along the passages 8 to the nozzle orifice 2 and from thereemerges in the form of a conical atomized body 13.

In the arrangement shown in FIGS. 3 and 4, parts that are similar tothose shown in FIGS. 1 and 2 are designated by the same referencenumerals as those used in these latter Figures. An insertable shell 14made of sintered material is used in the arrangement shown in FIGS. 3and 4. Three grooves 15 are formed on the inside of this shell and thesegrooves run from the rear end face 16 to an orifice 17 in the front endface 18. These grooves are covered by the nozzle cone 5 and form thepassages. The grooves 15 could also be on the exterior of the shell 14and could be covered by the backing face 4.

We claim:

1. An atomizing nozzle comprising a tubularly shaped housing having abore and an outlet orifice at one end thereof, means forming afrustoconically shaped female backing surface, a frustoconically shapedshell engaging said backing surface, a member having a frustoconicallyshaped male surface, said male surface being in abutting engagement withsaid shell, radially extending passages between said surfaces formed bysaid shell and at least one of said surfaces, said member having a shankportion of lesser diameter than said bore to form an insertable shellannular distributing-chamber having fluid communication.

with said passages.

2. A nozzle according to claim 1 wherein said passages have the form ofslots in said shell and are formed in part by one of said male andfemale surfaces.

3. A nozzle according to claim 1 wherein said radially extendingpassages are partially defined by recessed grooves in said shell and oneof said surfaces.

4. A nozzle according to claim 3 wherein said one of said surfaces issaid male surface.

I n at in

1. An atomizing nozzle comprising a tubularly shaped housing having abore and an outlet orifice at one end thereof, means forming afrustoconically shaped female backing surface, a frustoconically shapedshell engaging said backing surface, a member having a frustoconicallyshaped male surface, said male surface being in abutting engagement withsaid shell, radially extending passages between said surfaces formed bysaid shell and at least one of said surfaces, said member having a shankportion of lesser diameter than said bore to form an annulardistributing chamber having fluid communication with said passages.
 2. Anozzle according to claim 1 wherein said passages have the form of slotsin said shell and are formed in part by one of said male and femalesurfaces.
 3. A nozzle according to claim 1 wherein said radiallyextending passages are partially defined by recessed grooves in saidshell and one of said surfaces.
 4. A nozzle according to claim 3 whereinsaid one of said surfaces is said male surface.